(1) Field of the Invention
This invention relates to a typed test processing and data communications system, and more particularly to a combined communicating typewriter/dictation system which utilizes a common modem to both demodulate and remodulate analog tones transmitted between the mass media recorder of the instant system and a remote system.
(2) Prior Art
Generally, recording devices in word processing environments utilize digital recording techniques. For example, the recorder described in U.S. Pat. No. 3,528,063 utilizes a digital recording technique because of the high densities obtainable with this type of recording. However, one current drawback to the use of this recording technique is cost. The cost of digital logic when compared to the recording rate is balanced only when the density of the recording rate is high and the error rate is low.
Moreover, the system described in U.S. Pat. No. 3,528,063 transmits and receives data that is digital in form. The logic needed to perform this function increases the cost of the system. A problem encountered in digital signal transmission is bit dropout, which increases the possibility of an erroneous transmission.